1. Field of the Invention
The present invention relates to a personal communication method and system for establishing communications based on a unique personal number assigned to each subscriber.
2. Description of the Prior Art
Recently, personal communications have been more and more popular for their noticeable utility. Personal communications can be established by assigning a unique personal number to each subscriber and specifying by a source subscriber the personal number of a destination subscriber wherever the destination subscriber is when he or she is called.
The personal communications enable a source subscriber to communicate with any destination subscriber wherever the destination subscriber is when he or she is called, thereby guaranteeing personal mobility and realizing communications with any subscriber regardless of the type of network.
To successfully establish personal communications, unique personal numbers and the related location information, etc. should be stored in a data base. However, if personal information is centrally managed in one data base, it takes much time to retrieve target personal information, thus causing difficulty in establishing real-time communications.
Then, a plurality of data bases are assumed to store personal information separately. In this case, target personal information must be easily accessed and retrieved from the right data base. To attain this, a new data base accessing method has been developed by providing a directory server for informing which data base contains the target personal information so that the address of the data base can be retrieved from the directory server.
FIG. 1 shows the access sequence according to which the above described data base accessing method is carried out.
When a subscriber specifies a source identifier (ID) (a personal number of a source subscriber) and a destination ID (a personal number of a destination subscriber), a switching unit first retrieves from a directory server the address of the personal information data base (DB) storing the personal information on the source according to the source ID, and gets information from the data base whether or not the source is registered as a subscriber. Then, it retrieves from the directory server the address of the personal information data base storing the personal information on the destination subscriber according to the destination ID, gets the destination location information from the corresponding data base, and performs a routing process according to the location information.
However, a method of retrieving a data base storing target personal information in the above described directory server requires time for retrieving necessary information in a directory server and a data base. Therefore, with the increasing subscribers and total retrieval time in a directory server, it becomes very difficult to perform real-time call processes.
On the other hand, the noticeable utility pertaining to the personal communications that the communications can be established wherever a destination subscriber is may be the problem for the destination subscriber that the privacy of the destination subscriber can be violated by a call when he or she does not want to accept it, or that the subscriber is subject to a malicious call. Therefore, a countermeasure is demanded to realize call reception control performed by a destination subscriber so that the destination subscriber's undesirable call can be rejected.
Furthermore, with the conventional personal communications, a unique personal number must be assigned to each subscriber in the world. Accordingly, a personal number is represented by not a few digits, and subscribers often get into trouble of memorizing and entering all the digits in making a call.